Does the psu work, the signals look ok to me, the main signals to look for are B ,E they look like they are working, C will be near enough at Zero as its a current monitor signal, D will be at the supply of the IC as its a DC take over winding from the pulse transformer, A,B should be nearly the same square wave pulses, and the signal on pin 1 will be the shut down signal from the opto coupler.

Yes, the power supply works, I was just thrown off by that ringing... I expected a square signal at E. Can you tell me how that ringing comes to be? Especially little one on the top of the signal graph and larger one after that?

This high frequency ringing (little one on the top of the signal graph ) are caused by primary winding leaking inductance and MOSFET parasitic capacitance.
The low frequency ringing are caused by primary winding inductance and MOSFET parasitic capacitance. But this is quite normal, so no worries.